Abstract

We experimentally study the behavior of an electromagneticshock wave radiated by a picosecond electrical pulse propagating on a coplanar stripline at the interface between air and a GaAs substrate. The shock wave is directly measured by time-resolved electroabsorption sampling. We show that after a few millimeters of propagation this shock wave is in fact constituted by substrate modes causing large leakage resonances in the spectrum of the propagating pulse. At last, we show that the presence of adjacent transmission lines on the substrate has an influence on these leakage resonances.